This invention relates to pyranone compounds and skin-lightening (bleaching) cosmetic preparations or local demelanizing agents containing the same.
It has been a woman's desire to keep the face and skin fair and remove liver-spots caused on the face or skin. Therefore, a wide variety of substances and minerals have been used for the purpose. Cosmetic preparations and local demelanizing agents containing various peroxides, peroxy compounds such as peroxysulfates and peroxyborates or reducing agents such as vitamin C, cysteine and colloidal sulfur have been developed and used commonly even in recent years. All these substances, however, have problems related to safety and effectiveness, and satisfactory results have not been attained.
Thus, the advent of novel skin-lightening cosmetic preparations or local demelanizing agents which correct the above-mentioned disadvantages of the conventional cosmetic preparations and demelanizing agents and have the following advantages has been sought:
(a) exhibiting no toxicity to the human body; PA1 (b) capable of remarkable skin-lightening and sunscreening effects; and PA1 (c) positively effective against liver-spots.